The
CoraciiformesCoraciiformes are a group of usually colorful birds including the
kingfishers, the bee-eaters, the rollers, the motmots, and the todies.
They generally have syndactyly, with three forward-pointing toes (and
toes 3 & 4 fused at their base), though in many kingfishers one of
these is missing.
This is largely an
Old WorldOld World order, with the representation in the New
World limited to the dozen or so species of todies and motmots, and a
mere handful of the more than a hundred species of kingfishers.
The name
CoraciiformesCoraciiformes means "raven-like", which is a misnomer (ravens
are passerines). Specifically, it comes from the Latin language
"corax", meaning "raven" and Latin "forma", meaning "form", which is
the standard ending for bird orders.[1]

This order has been seen to be something of a mixed assortment, and
the
CoraciiformesCoraciiformes may be considered as including only the rollers. All
the other families would then be considered to represent lineages of
birds distantly related to Coraciiformes. This seems to be
oversplitting, as most
CoraciiformesCoraciiformes indeed form a reasonably robust
clade.
Analysis of nDNA c-myc and
RAG-1 exon as well as mtDNA myoglobin
intron 2 sequence data demonstrates that the
CoraciiformesCoraciiformes can be
divided into a basal group that is not too distantly related to the
Piciformes, and a derived suborder containing mainly kingfishers
(Johansson & Ericson, 2003). The cuckoo roller's true affinities
appear to lie elsewhere[citation needed]. The trogons and hornbills
are either very basal lineages, or might be considered distinct own
orders; the latter are apparently slightly closer to the rollers than
the former. The entire group (possibly excluding the cuckoo roller)
and the
PiciformesPiciformes are closely related to the
PasseriformesPasseriformes (Johansson
& Ericson 2003; see also near passerine).
Several extinct coraciiform families are only known from Paleogene
fossils. They probably belong to the basal group and are sometimes
difficult to assign because they were even closer still to the
PiciformesPiciformes (see also Neanis). In addition, there are some prehistoric
genera which are likewise difficult to place into a family. At least
the Eocoraciidae are very basal, but the Late
EoceneEocene (some 35 mya)
Geranopteridae form a superfamily Coracioidea with the extant rollers
and ground-rollers already (Mayr & Mourer-Chauviré 2000). A few
prehistoric taxa of the present-day families have been described; see
the family articles for details.
Taxonomic sequence[edit]
Unresolved

The
LeptosomatidaeLeptosomatidae (cuckoo roller) probably do not belong here. The
trogons are sometimes placed here as a family Trogonidae. The Late
EoceneEocene Palaeospizidae are sometimes also placed in the Coraciiformes,
as are the Early to
Middle EoceneMiddle Eocene Primobucconidae and the Middle
EoceneEocene to Early Oligocene Sylphornithidae. The Primobucconidae at
least indeed seem to belong here.
Basal group